A discrete-time wireless receiver including a switched capacitor circuit has a high configurability. The discrete-time wireless receiver needs to eliminate noise. In a high-frequency domain applied to radio, noise is primarily thermal noise. The amplitude of noise approximates to a normal distribution.
In the case where the amplitude of noise contained in a signal approximates to a normal distribution, a number of signal values (samples) of the signal are sampled to determine an average value, so that the noise (noise power) contained in the signal can be reduced.
As an averaging circuit which determines an average value of N (a natural number of 2 or more) signal values, an averaging circuit employing N sampling switches and N capacitors is known.